Changing Light Cycle Becuase Of Heat

Hi. I have 6 auto ww and amnesia auto. I kept on 24/7 full veg stage and then i changed flowerin 20/4 which was okay. Where i live gets so hot this time of the year and then i changed 19-6 for one more less day time hotness. Point is it gets hotter now if i changin it one more to 18-6 would stress the plant. Light lekas rule same for autos ?

Autos dont care about light leaks. Moving to 18-6 or even less should be fine. You can grow autos outside just fine....days get longer...days get shorter....